OBJECTIVES: We sought to determine whether social class modifies the effect of BMI on breast cancer incidence. METHODS: Participants included 5642 postmenopausal White women recruited in 1989 to CLUE II, a prospective cohort study in Washington County, Maryland. We obtained exposure data from CLUE II and the 1990 US Census. We used survival and random-effects Cox proportional hazards analyses to determine the association of social class and BMI with breast cancer incidence. RESULTS: Education was independently associated with increased risk of breast cancer incidence (hazard ratio [HR]=1.06; 95% confidence interval [CI]=1.01, 1.11; P<.05); contextual measures of social class were not. Education modified the effect of BMI at age 21 years (HR=0.98; 95% CI=0.97, 0.99); area-level social class modified the effect of BMI at baseline (HR=0.97; 95% CI=0.94, 0.99) and BMI change (HR=0.98; 95% CI=0.95, 1.00). Subpopulation analyses that were adjusted for hormone use, parity, and breast-feeding found similar effects. CONCLUSIONS: Social class moderates the influence of body size on breast cancer incidence. Public health efforts, therefore, should advocate for policies that improve social conditions to decrease the burden of breast cancer.
OBJECTIVES: We sought to determine whether social class modifies the effect of BMI on breast cancer incidence. METHODS:Participants included 5642 postmenopausal White women recruited in 1989 to CLUE II, a prospective cohort study in Washington County, Maryland. We obtained exposure data from CLUE II and the 1990 US Census. We used survival and random-effects Cox proportional hazards analyses to determine the association of social class and BMI with breast cancer incidence. RESULTS: Education was independently associated with increased risk of breast cancer incidence (hazard ratio [HR]=1.06; 95% confidence interval [CI]=1.01, 1.11; P<.05); contextual measures of social class were not. Education modified the effect of BMI at age 21 years (HR=0.98; 95% CI=0.97, 0.99); area-level social class modified the effect of BMI at baseline (HR=0.97; 95% CI=0.94, 0.99) and BMI change (HR=0.98; 95% CI=0.95, 1.00). Subpopulation analyses that were adjusted for hormone use, parity, and breast-feeding found similar effects. CONCLUSIONS: Social class moderates the influence of body size on breast cancer incidence. Public health efforts, therefore, should advocate for policies that improve social conditions to decrease the burden of breast cancer.
Authors: Shannon M Conroy; Christina A Clarke; Juan Yang; Salma Shariff-Marco; Yurii B Shvetsov; Song-Yi Park; Cheryl L Albright; Andrew Hertz; Kristine R Monroe; Laurence N Kolonel; Loïc Le Marchand; Lynne R Wilkens; Scarlett Lin Gomez; Iona Cheng Journal: Cancer Epidemiol Biomarkers Prev Date: 2017-01-31 Impact factor: 4.254
Authors: Ann C Klassen; Aaron Pankiewicz; Stephanie Hsieh; Abigail Ward; Frank C Curriero Journal: Int J Health Geogr Date: 2015-04-01 Impact factor: 3.918
Authors: Shannon M Conroy; Salma Shariff-Marco; Jocelyn Koo; Juan Yang; Theresa H M Keegan; Meera Sangaramoorthy; Andrew Hertz; David O Nelson; Myles Cockburn; William A Satariano; Irene H Yen; Ninez A Ponce; Esther M John; Scarlett Lin Gomez Journal: Cancer Epidemiol Biomarkers Prev Date: 2017-02-14 Impact factor: 4.090